A gas turbine engine can comprise a combustion chamber, wherein fuel is mixed with air to generate hot combustion gasses, and a turbine, wherein the gasses are expanded and energy extracted therefrom. A turbine will often comprise an assembly (e.g., a nozzle assembly, a shroud assembly, etc.) constructed from a plurality of segments circumferentially adjoined to form a circular array. Interfacing circumferential parts of the segments commonly have opposed slots, which together form a pocket (having a floor and a ceiling). A seal is installed in the pocket to prevent leakage in a path substantially perpendicular to its floor and ceiling.